Engineering Commons^™

Behavior Of Segmental Precast Posttensioned Bridge Piers Under Lateral Loads, Haitham Dawood, Mohamed Elgawady, Joshua Hewes

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Abstract a segmental precast posttensioned (SPPT) bridge pier is an economic recentering structural system. Understanding the seismic behavior of a SPPT system is an important step toward its application in high seismic zones. This paper presents a detailed three-dimensional finite-element (FE) model that was developed using the ABAQUS platform. a brief description and discussion of cyclic tests on eight large-scale SPPT piers is also presented. Four of the piers were constructed and tested to a predefined degree of damage. Then, these piers were retrofitted and retested. the FE models developed and presented in this paper predicted the backbone curves of …

Learjet 23 Donated To Department Of Aviation, Ashley Meyer

Lake Union Herald

No abstract provided.

Investigation Of A New Material For Heart Valve Tissue Engineering, Claire Brougham, Gerard Cooney, Thomas Flanagan, Stefan Jockenhoevel, Fergal O'Brien

Conference Papers

No abstract provided.

Analysis Of Traffic Crash Data In Kentucky (2007-2011), Eric R. Green, Kenneth R. Agent, Jerry G. Pigman

Kentucky Transportation Center Research Report

This report documents an analysis of traffic crash data in Kentucky for the years of 2007 through 2011. A primary objective of this study was to determine average crash statistics for Kentucky highways. Average and critical numbers and rates of crashes were calculated for various types of highways in rural and urban areas. These data can be used in Kentucky’s procedure to identify locations that have abnormal rates or numbers of crashes.

Maximal Force Characteristics Of The Ca2+-Powered Actuator Of Vorticella Convallaria, Sangjin Ryu, Matthew J. Lang, Paul Matsudaira

Department of Mechanical and Materials Engineering: Faculty Publications

The millisecond stalk contraction of the sessile ciliate Vorticella convallaria is powered by energy from Ca²⁺ binding to generate contractile forces of ~10 nN. Its contractile organelle, the spasmoneme, generates higher contractile force under increased stall resistances. By applying viscous drag force to contracting V. convallaria in a microfluidic channel, we observed that the mechanical force and work of the spasmoneme depended on the stalk length, i.e., the maximum tension (150–350 nN) and work linearly depended on the stalk length (~2.5 nN and ~30 fJ per 1 mm of the stalk). This stalk-length dependency suggests that motor units of …

Low Power Data Acquisition For Microimplant Biometric Monitoring Of Tremors, Tania Khanna '01

Doctoral Dissertations

In recent years, trends in the medical industry have created a growing demand for implantable medical devices. In particular, the need to provide doctors a means to continuously monitor biometrics over long time scales with increased precision is paramount to efficient healthcare. To make medical implants more attractive, there is a need to reduce their size and power consumption. Small medical implants would allow for less invasive procedures, greater comfort for patients, and increased patient compliance. Reductions in power consumption translate to longer battery life. The two primary limitations to the size of small medical implants are the batteries that …

Stochastic Reactor Modelling Of Multi Modes Combustion With Diesel Direct Injection Or Hydrogen Jet Ignition Start Of Combustion, Alberto A. Boretti

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Recent papers [1-5] have proposed two different systems to more efficiently and more rapidly burn the fuel in highly boosted, high compression ratio, directly injected internal combustion engines permitting multi-mode combustion operation. in a first system, a second direct injector is coupled with the standard Diesel direct injector and glow plug. the second direct injector introduces most of the fuel while the Diesel direct injector only introduces a minimum amount of fuel to control the start of the combustion about top dead center. the fuel injected before the Diesel ignition injection burns premixed, the fuel injected after the Diesel ignition …

Optimal Slewing Of A Constrained Telescope Using Seventh Order Polynomial Input Torques, Julia K. Bush

Master's Theses

Two-axis gimbals are frequently used to point cameras and telescopes at various points of interest for surveillance, science, and art. The rotation of a two-axis gimbal system is governed by nonlinear angular momentum equations of motion. This paper presents a method for slewing a telescope in space with a gimbaled sensor attached to a nominally non-rotating spacecraft using two seventh order polynomial input functions to characterize torques. To accomplish this task, picking the optimal coefficients of the seventh order polynomial was necessary. It was also desired to use constraint equations to limit the excursion, angular velocity, angular acceleration, and jerk …

Responding To Dangerous Accidents Among The Elderly: A Fall Detection Device With Zigbee-Based Positioning, Michael R. Putnam

Master's Theses

The following paper describes a fall detection and activity monitoring system with position detection based on Zigbee transceivers.The main objective is to reduce the time taken for emergency personnel to respond to falls among the elderly. Especially when the victim is unconscious or delirious, position tracking reduces location determination time within a busy hospital or nursing home environment and facilitates immediate treatment. Reduced response times correlate to decreased morbidity and mortality rates. Background is provided on the major wireless network advances currently deployed in a healthcare setting for asset and personnel tracking, etiology of falls, and several methods of detecting …

Identification Of Orbital Objects By Spectral Analysis And Observation Of Space Environment Effects, Jason B. Rapp

Master's Theses

This report presents an investigation and development of the methods for orbital object identification. Two goals were accomplished in this master’s thesis; the development of a method of inverting material proportions from an object’s combined spectrum, and the investigation of methods and initialization of measurement of space environment effects on spectral features of common spacecraft materials. A constrained least squares approach was chosen for inverting spectral proportions from the combined spectra. The final results fall within 1 - 15% of the original spectrum, depending on the quality and noise levels of the original spectrum. Additionally, the effects of outgassing and …

Me-Em Enewsbrief, September 2012, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.

Probabilistic Analysis Of Indeterminate Highway Bridges Considering Material Nonlinearity, Liam Mccarthy

Masters

With ever-reducing maintenance budgets and ever-deteriorating bridge infrastructure, th assessment of existing bridges is vital. Reliability analysis techniques are becomin increasingly popular in the structural safety assessment of existing bridge structures Commonly, a component based approach is used in reliability analysis techniques Traditional reliability procedures often employ a conservative definition of failure, in that th component is deemed to have failed when the strength capacity has been exceeded at a singl cross section. As a result, the component's degree of redundancy and ductility is ignored giving an often conservative estimate of the load carrying capacity of the bridge component Therefore, …

Quaternary Ammonium Silane-Functionalized, Methacrylate Resin Composition With Antimicrobial Activities And Self-Repair Potential, Shi-Qiang Gong, Li-Na Niu, Lisa K. Kemp, Cynthia K.Y. Yiu, Heonjune Ryou, Yi-Pin Qi, John D. Blizzard, Sergey Nikonov, Martha G. Brackett, Regina L.W. Messer, Christine D. Wu, Jing Mao, L. Bryan Brister, Frederick A. Rueggeberg, Dwayne D. Arola, David H. Pashley, Franklin R. Tay

Faculty Publications

The design of antimicrobial polymers to address healthcare issues and minimize environmental problems is an important endeavor with both fundamental and practical implications. Quaternary ammonium silane-functionalized methacrylate (QAMS) represents an example of antimicrobial macromonomers synthesized by a sol–gel chemical route; these compounds possess flexible Si–O–Si bonds. In present work, a partially hydrolyzed QAMS co-polymerized with 2,2-[4(2-hydroxy 3-methacryloxypropoxy)-phenyl]propane is introduced. This methacrylate resin was shown to possess desirable mechanical properties with both a high degree of conversion and minimal polymerization shrinkage. The kill-on-contact microbiocidal activities of this resin were demonstrated using single-species biofilms of Streptococcus mutans (ATCC 36558), Actinomyces naeslundii (ATCC …

The Unprecedented Assimilation Of Mobile Telephony In Ireland: A Phenomenon Of The Celtic Tiger Era Or A Result Of Cultural Traits?, Andreas Scheibelhut

Masters

Following the universal acceptance of mobile telephony the once elitist gadget has become an indispensable democratic tool of everyday communications over the last three decades. Controversially, this thesis illustrates that its level of both adoption and usage did not develop in a similar homogenous pattern in selected OECD countries. In particular, the Irish performance is rather astonishing given the speed of adoption as well as the exceptional high revenue figures achieved by the wireless operators. Consequently, this work determines a selection of factors that drive and encourage both the adoption and usage of cellular telephony in Ireland. The Irish experience …

An Analysis Of The Impacts Of Temperature Segregation On Hot Mix Asphalt, Thaddaeus A. Bode

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

This research was conducted to produce a more realistic picture of how variables are created and dealt with during hot mix asphalt (HMA) paving construction. Several paving projects across the State of Nebraska have been visited where sensing devices were used to test how the selected variables contribute to temperature differentials. These variables include density, moisture content within the asphalt, material surface temperature, internal temperature, wind speed, haul time, and equipment type. Areas of high temperature differentials are identified using an infrared camera whose usefulness was initially confirmed with a penetrating thermometer. A non-nuclear density device was also used to …

Design And Characterization Of Asymmetric Cross-Linked Polymer Membranes By Molecular Dynamics Modeling And Simulations, Jee-Ching Wang, Athanasios I. Liapis

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

Stochastic Simulation Of Entangled Polymeric Liquids In Fast Flows: Microstructure Modification, Joontaek Park, David W. Mead, Morton M. Denn

Chemical and Biochemical Engineering Faculty Research & Creative Works

We have modified the full-chain stochastic tube (XDS) model developed by Xu et al. [J. Rheol. 50, 477-494 (2006)] to simulate the rheology of entangled melts and solutions of linear monodisperse polymers. The XDS model, which has a single adjustable parameter that is equivalent to the Rouse time, successfully describes steady and transient shear and normal stress data at low to moderate rates, but the results deviate systematically from experimental data at high rates. The algorithm for re-entanglement was revised, and a configuration- dependent friction coefficient (CDFC), as originally proposed by Giesekus, was incorporated to account for microstructural change of …

Creep Evaluation Of (Orthotic) Cast Materials During Simulated Clubfoot Correction, T. L. Cohen, H. Altiok, Sergey Tarima, P. A. Smith, Gerald F. Harris

Biomedical Engineering Faculty Research and Publications

The Ponseti method is a widely accepted and highly successful conservative treatment of pediatric clubfoot that relies on weekly manipulations and cast applications. However, the material behavior of the cast in the Ponseti technique has not been investigated. The current study sought to characterize the ability of two standard casting materials to maintain the Ponseti corrected foot position by evaluating creep response. A dynamic cast testing device (DCTD) was built to simulate a typical pediatric clubfoot. Semi-rigid fiberglass and rigid fiberglass casting materials were applied to the device, and the rotational creep was measured at various constant torques. The movement …

Structural Performance And Economics Of High-Rise Buildings Under Seismic And Wind Loads, Nadeem Hussain

Theses

High-rise buildings have a priority when considering the potential consequences from natural hazards since they represent concentrated human and monetary assets. The use of high strength materials is promoted in this class of structures to effectively use floor areas, control vibrations and expedite construction. There is a pressing need to investigate the relationship between structural performance and economics of high-rise buildings with different material strengths under lateral loads, particularly seismic loads that control the design of a wide range of buildings.

To realistically represent the modern high-rise construction, five 60-story reinforced concrete (RC) buildings with varying material strengths, ranging from …

Bs News September/October

Building Services Engineering

No abstract provided.

Analysis Of A Goldschmied Propulsor Using Computational Fluid Dynamics Referencing California Polytechnic's Goldschmied Propulsor Testing, Cory A. Seubert

Master's Theses

The Goldschmied Propulsor is a concept that was introduced in mid 1950's by Fabio Goldschmied. The concept combines boundary layer suction and boundary layer ingestion technologies to reduce drag and increase propulsor efficiency. The most recent testing, done in 1982, left questions concerning the validity of the results. To answer these questions a 38.5in Goldschmied Propulsor was constructed and tested in Cal Poly's 3x4ft wind tunnel. The focus of their wind tunnel investigation was to replicate Goldschmied's original testing and increase the knowledge base on the subject. The goal of this research was to create a computational fluid dynamics (CFD) …

Scalable Distributed Communication Architectures To Support Advanced Metering Infrastructure In Smart Grid, Jian Zhou, Rose Qingyang Hu, Yi Qian

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

In this paper, we investigate the scalability of three communication architectures for advanced metering infrastructure (AMI) in smart grid. AMI in smart grid is a typical cyber-physical system (CPS) example, in which large amount of data from hundreds of thousands of smart meters are collected and processed through an AMI communication infrastructure. Scalability is one of the most important issues for the AMI deployment in smart grid. In this study, we introduce a new performance metric, accumulated bandwidth distance product (ABDP), to represent the total communication resource usages. For each distributed communication architecture, we formulate an optimization problem and obtain …

Value Of Travel Time Reliability Part Ii: A Study Of Tradeoffs Between Travel Reliability, Congestion Mitigation Strategies And Emissions, Miguel A. Figliozzi, Alexander Y. Bigazzi

Civil and Environmental Engineering Faculty Publications and Presentations

Capacity, demand, and vehicle based emissions reduction strategies are compared for several pollutants employing aggregate US congestion and vehicle fleet condition data. We find that congestion mitigation does not inevitably lead to reduced emissions; the net effect of mitigation depends on the balance of induced travel demand and increased vehicle efficiency that in turn depend on the pollutant, congestion level, and fleet composition. In the long run, capacity-based congestion improvements within certain speed intervals can reasonably be expected to increase emissions of CO2e, CO, and NOx through increased vehicle travel volume. Better opportunities for emissions reductions exist for HC and …

General Aviation Weather Encounter Case Studies, John M. Lanicci, Massoud Bazargan, Daniel Halperin, Scott Shappell, Jaclyn Baron, Rebecca Iden, Carla Hackworth, Kali Holcomb

School of Graduate Studies - Daytona Beach

This study presents a compilation of 24 cases involving general aviation (GA) pilots’ weather encounters over the continental U.S. The project team interviewed pilots who had experienced a weather encounter, and we examined their backgrounds, flight experience, and weather encounter details. Results from meteorological data analysis for each weather encounter were consistent with findings of larger GA weather accident studies in terms of the types of hazards encountered and flight phase during which the encounters occurred. Investigation of pilot weather products and the sources from which they were obtained revealed a lack of uniformity of pre-flight data sources and underutilization …

Phase Transitions Of Nanoemulsions Using Ultrasound: Experimental Observations, Ram Singh, Ghaleb A. Husseini, William G. Pitt

Faculty Publications

The ultrasound-induced transformation of perfluorocarbon liquids to gases is of interest in the area of drug and gene delivery. In this study, three independent parameters (temperature, size, and perfluorocarbon species) were selected to investigate the effects of 476-kHz and 20-kHz ultrasound on nanoemulsion phase transition. Two levels of each factor (low and high) were considered at each frequency. The acoustic intensities at gas bubble formation and at the onset of inertial cavitation were recorded and subsequently correlated with the acoustic parameters. Experimental data showed that low frequencies are more effective in forming and collapsing a bubble. Additionally, as the size …

Heuristic Algorithms For Optimization Of Task Allocation And Result Distribution In Peer-To-Peer Computing Systems, Grzegorz Chmaj, Krzysztof Walkowiak, Michal Tarnawski, Michal Kucharzak

Electrical & Computer Engineering Faculty Research

Recently, distributed computing system have been gaining much attention due to a growing demand for various kinds of effective computations in both industry and academia. In this paper, we focus on Peer-to-Peer (P2P) computing systems, also called public-resource computing systems or global computing systems. P2P computing systems, contrary to grids, use personal computers and other relatively simple electronic equipment (e.g., the PlayStation console) to process sophisticated computational projects. A significant example of the P2P computing idea is the BOINC (Berkeley Open Infrastructure for Network Computing) project. To improve the performance of the computing system, we propose to use the P2P …

Optimal Reduction Of Electrical Energy Consumption By Supply Air Ac Motors, Keyhan Rafiee

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

The Nebraska Center for Energy Sciences Research (NCER) at the University of Nebraska-Lincoln (UNL) strives to be energy efficient through Green Energy. Of course, in meeting some of the requirements for different types of Leadership in Energy and Environmental Design (LEED) certification, certain minimum levels of energy efficiency practices must be met. One such level of energy efficiency, in particular, is reduction in the consumption of electrical energy in buildings. This thesis is a study of methods of reducing the consumption of electrical energy (measured in kW of electrical power) in the UNL Jorgensen Hall (JH) air handling unit 2 …

Leveraging Whole Life Cycle Costs When Utilising Building Information Modelling Technologies, Barry Mcauley, Dermot Kehily, Alan Hore

Conference papers

Building Information Modelling (BIM) is now being increasingly used as a technology tool to assist design professions in conceiving, designing, constructing, and operating the built environment in many countries. The BIM model provides design professions with the framework to perform exercises in design, programming, cost and value management, and concept energy analysis, in order to achieve the most economical and sustainable building solution. The BIM model though sophisticated is not extensively used to provide estimation software with the data requirements for Life Cycle Costing (LCC), such as, escalation of future expenditure and/or present value costs, discount rates, and study periods. …

Noise Impacts From Professional Dog Grooming Forced-Air Dryers, Peter M. Scheifele, Michael T. Johnson, David C. Byrne, John G. Clark, Ashley Vandlik, Laura W. Kretschmer, Kristine E. Sonstrom

Electrical and Computer Engineering Faculty Research and Publications

This study was designed to measure the sound output of four commonly used brands of forced-air dryers used by dog groomers in the United States. Many dog groomers have questions about the effect of this exposure on their hearing, as well as on the hearing of the dogs that are being groomed. Readings taken from each dryer at 1 meter (the likely distance of the dryer from the groomer and the dog) showed average levels ranging from 105.5 to 108.3 dB SPL or 94.8 to 108.0 dBA. Using the 90 dBA criterion required by the US Occupational Safety and Health …

An Alternative Dual-Launch Architecture For A Crewed Asteroid Mission, Steven M. Korn

Master's Theses

This thesis is a feasibility study for a crewed mission to a Near Earth Asteroid (NEA). An alternate dual-launch architecture is proposed and analyzed against a more established architecture. Instead of a rendezvous in a low-Earth parking orbit, the new architecture performs the rendezvous while the two spacecraft are on an Earth-escape trajectory to the destination NEA. After selecting a target asteroid, 2000 SG344, each architecture will have its best mission compared to the best mission of the other architecture.

Using the new architecture, a mission is created to the chosen NEA, 2000 SG344. A back-up Orion MPCV and a …